As described in PTL 1, there is a conventional oil pressure control apparatus, including: a pump that ejects oil by being driven by the rotation of an engine (an “oil pump” in this document); a valve timing control device having a driving-side rotatable member (an “outer rotor” in this document) that rotates in synchronization with a crankshaft and a following-side rotatable member (an “inner rotor” in this document) that is disposed in coaxial with the driving-side rotatable member and that rotates in synchronization with a camshaft, wherein a relative rotational phase of the following-side rotatable member with respect to the driving-side rotatable member is displaced according to supply or discharge of oil; and an engine lubricating device that lubricates constituent portions in the engine using the oil supplied by the pump.
The invention described in PTL 1 includes a flow passage area adjusting portion (a “priority valve” in this document) that, when the pressure of oil acting on the valve timing control device is low, limits the flow rate of oil from the pump to the engine lubricating device, thereby giving priority to the oil supply from the pump to the valve timing control device. Accordingly, the pressure of oil acting on the valve timing control device is ensured on a priority basis when the number of rotations of the pump is low, and, thus, the valve timing control device can be properly actuated without an electrically-driven pump for assisting the pump.